The Supreme Court unanimously ruled on Thursday that human genes can not be patented .

But in something of a compromise , all nine justices said while the naturally occurring isolated biological material itself is not patentable , a synthetic version of the gene material may be patented .

Legal and medical experts believe the decision will have a lasting impact on genetic testing , likely making varieties more widely available and more affordable .

The overriding legal question addressed was whether `` products of nature '' can be treated the same as `` human-made '' inventions , allowing them to be held as the exclusive intellectual property of individuals and companies .

The broader issue involved 21st century conflicts over cutting-edge medical science , the power of business and individual legal rights , and how their convergence might influcence decisionmaking over how people and medicine manage the prospect and reality of certain diseases , like cancer .

The issue has deeply divided the scientific and business communities . But it was a blockbuster celebrity , actress Angelina Jolie who brought it to the public in announcing last month that she underwent a double mastectomy following a genetic test .

The Supreme Court case involves Myriad Genetics , a Utah-based company that was sued over its claim of patents relating to two types of biological material that it identified -- BRCA1 and BRCA2 , whose mutations are linked to increased hereditary risk for breast and ovarian cancer .

Since Myriad owns the patent on breast cancer genes , it was the only company that could perform tests for potential abnormalities .

It says 1 million patients have benefited from its `` BRAC Analysis '' technology , and that about 250,000 such tests are performed yearly .

An initial test catches most problems , but the company also offers a second called BART to detect the rest , a diagnostic that can cost several thousand dollars .

Jolie had Myriad 's breast cancer test .

Plaintiffs and testing

Among those challenging the Myriad patents were sisters Eileen Kelly and Kathleen Maxian . Kelly was diagnosed with breast cancer at age 40 .

The initial BRCA test proved negative , meaning her family members were not likely at risk . But Maxian later developed ovarian cancer . The second BART testing proved positive , meaning the siblings carried the cancer-causing mutation all along .

Money was not an issue for them , but Kelly and Maxian , along with a coalition of physician groups and genetic counselors say Myriad has not made the BART tests widely available for patients without a strong family history of these kinds of cancers .

Breast cancer survivor Lisbeth Ceriani was another plaintiff . She faced having to pay thousands for Myriad 's test to see if she had a mutation for ovarian cancer . Because of cost , she waited 18 months before she could afford it , learning she carried a mutation , according to the American Civil Liberties Union , which represented plaintiffs .

All sides agree the science of isolating the building blocks of life is no easy task . Myriad has said it has spent several years and hundreds of millions of dollars in its research . But the issue of patenting has divided the scientific and business communities .

A history of patent protection

In the past 31 years , 20 percent of the human genome has been protected under U.S. patents .

On one side of the Myriad case , scientists and companies argued patents encourage medical innovation and investment that saves lives .

On the other , patient rights groups and civil libertarians countered the patent holders were `` holding hostage '' the diagnostic care and access of information available to high-risk patients .

Outside the court during oral arguments in April , several protesters held signs , such as `` Your corporate greed is killing my friends '' and `` My genes are not property . ''

The patent system was created more than two centuries ago with a dual purpose . One is to offer temporary financial incentives for those at the ground floor of innovative products like the combustible engine and the X-ray machine .

The second is to ensure one company does not hold a lifetime monopoly that might discourage competition and consumer affordability .

All patent submissions rely on a complex reading of applicable laws , distinguishing between abstract ideas and principles , and more tangible scientific discoveries and principles .

The Supreme Court ruling

The Supreme Court has long allowed patent protection for the creation of a new process or use for natural products . Whether `` isolating '' or `` extracting '' genes themselves qualifies for such protection became the central argument .

The justices took the position offered by the Obama administration -- DNA itself is not patentable but so-called `` cDNA '' can be .

Complementary DNA is artificially synthesized from the genetic template , and engineered to produce gene clones .

Use of this protein-isolating procedure , known as `` tagging , '' is especially important in mapping and cataloguing the vast human genome .

`` Genes and the information they encode are not patent-eligible under -LSB- federal law -RSB- simply because they have been isolated from the surrounding genetic material , '' said Justice Clarence Thomas , who wrote the 9-0 court opinion .

`` Myriad did not create anything , '' said Thomas . `` To be sure , it found an important and useful gene , but separating that gene from its surrounding genetic material is not an act of invention . ''

But Thomas said , `` cDNA does not present the same obstacles to patentability as naturally occurring , isolated DNA segments . ''

See also : Supreme Court backs DNA swab after arrest

Reaction to the decision

The American Civil Liberties Union said the decision represents a major shift in patent law and overturns established policy .

`` Today , the court struck down a major barrier to patient care and medical innovation , '' said Sandra Park , senior staff attorney with the ACLU Women 's Rights Project . `` Myriad did not invent the BRCA genes and should not control them . Because of this ruling , patients will have greater access to genetic testing and scientists can engage in research on these genes without fear of being sued . ''

Dr. Harry Ostrer , a professor at Albert Einstein College of Medicine and director of genetic and genomic testing at Montefiore Medical Center in New York , said the decision will not undermine the genetically engineered drug industry and expects the costs of tests to fall .

`` I 'm thrilled . We can offer BRCA 1 and 2 testing to low-income women without concerns about how it will be paid for , '' he said .

Jolie also hoped for a meaningful impact .

`` I hope that this ruling will lead to more women at risk of breast cancer being able to get access to gene testing and to take control of their lives , not just in the U.S. but around the world -- whatever their means and whatever their background , '' she said .

Peter D. Meldrum , president and chief executive officer of Myriad , said in a statement the company believed the court `` appropriately upheld our claims on cDNA ''

The ruling , he added `` underscored the patent eligibility of our method claims , ensuring strong intellectual property protection for our BRACAnalysis test moving forward . ''

Investors in Myriad were pleased with the ruling with the stock soaring as much as 9 % before settling back but still higher .

The case is Association for Molecular Pathology v. Myriad Genetics -LRB- 12-398 -RRB- .

2009 : How human genes became patented

2009 : ACLU sues over patents on breast cancer genes

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Unanimous ruling a compromise ; court says synthetic material , cDNA , can be patented

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Actress Angelina Jolie drove attention to the issue involving breast cancer

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Issue was whether `` products of nature '' could be treated similarly to human inventions

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Company at center of case says decision upheld a key claim on synthetic DNA